Bushings are known, for example, as electrical condenser bushings used in medium and high voltage electrical installations for leading a conductor through a grounded barrier (e.g., a metal wall of a transformer, tank or substation housing or similar).
Known bushings can include flanges made of metal, in particular of aluminium and can be expensive. In particular, the manufacturing process can be rather complicated. First, a core comprising an electrical field grading insulation and a test tap connection point is produced, e.g., by moulding and finished by machining. The expensive metal flange is produced separately and afterwards fixed to the core, such as with an adhesive, and an electrical connection with the test tap connection point established.